Indicating radiator closure



Feb. 13, 1968 J. CHRISTIAN 3,368,405

INDICATING RADIATOR CLOSURE Filed Dec. 7, 1965 INVLNToR Jo/r/z C/lr/sf/a/z Avior/26w United States Patent 3,368,405 INDICATING RADIATGR CLOSURE John Christian, 340 L.S.U. Ave., Baton Rouge, La. 70308 Filed Dec. 7, 1965, Ser. No. 512,095 5 Claims. (Cl. 73306) This invention relates to cooling systems for automobile engines, or other internal combustion engines of the liquid cooled type. More specifically, the invention relates to new and improved cap structures for radiators for internal combustion engines.

Practically all present day automobile engines, and other internal combustion engines of the liquid cooled type, employ coolant systems operating under pressure. In maintenance inspection to determine if more water is required in the cooling system, it is necessary to remove the cap and visually determine the liquid level. This is sometimes a hazardous operation, especially when the engine is at full operating temperature. As the entire supply of coolant liquid will be at a temperature above the normal boiling point, release of pressure on the system will result in considerable flashing of the superheated liquid, tending to spew out hot liquid and vapor. A serious need has existed for a radiator cap device which will allow determination of the need, or absence of need, for additional coolant, without actual removal of the radiator cap.

An object of the present invention is to provide a new and improved cap or closure for radiators of the type described. More specific objects will appear from the following description and from the accompanying figures, wherein:

FIG. 1 is a sectional elevation of one embodiment of the invention; and

FIG. 2 is a sectional elevation view of portions of another embodiment having certain special additional features.

A cap or closure of the present invention includes a cap structure similar to conventional caps with respect to threaded means for engaging the nozzle or spout of the radiator head tank. Mounted on the cap structure in a manner to be positioned, in use, in the radiator head tank, is a float-magnet assembly. This comprises a float element, such as a hollow body adapted to float on the surface of the liquid coolant within the radiator tank. Attached to the float is a permanent magnet, preferably at the upper surface of the float.

Above the float is a partition or barrier which is, or normally is, fluid tight, and forms part of the cap structure. Above said partition is provided an indicator assembly which is or includes a second permanent magnet and is loosely or slidably mounted in the cap structure for limited vertical movement. The said second magnet is oriented with a pole opposite a like pole of the float magnet. As the float magnet moves toward the second magnet, the latter is repelled vertically. Associated with the said second magnet are means responsive to its vertical movements and indicating its vertical position outside the cap. Various means are suitable for this purpose, but one suitable indicating means is an elongated element projecting above the cap top or upper extremity. The degree of projection will thus provide a visual guide to the coolant level in the radiator.

In most forms of the invention, features of previous closure structures can be and are desirably retained. Thus in various embodiments, pressure relief valve means are employed, or pressure relief and vacuum relief valve means.

Referring to FIGURE 1, a sectional view of one embodiment of the invention is shown in a nozzle 9 projecting from a radiator tank 8. An overflow tube 7 ex- 3,308,405 Patented Feb. 13, 1968 ice tends from the wall of the nozzle. The cap structure includes a top 21 provided with fingers 21a, 21b for engaging, in a screw-top fashion, corresponding flange portions 6a, 6b of the nozzle 9. A flexible metal sealant member 22 is pressed against the nozzle top when the top 21 is thus secured.

Actual closure of the radiator is accomplished by engagement of a resilient gasket 28. Sealing is accomplished by pressing the gasket 28 against a seat, formed by the nozzle interior, by the action of a spring 25 bearing on a flange member 27, which bears on a further flange member 29 to which the gasket 28 is attached.

The flange member 27 includes an internal flange section 26 capable of engaging a corresponding flange portion of a centrally positioned housing or cage 24 rigidly attached to the top member 21. Suitable attachment means can include brazing or, in this instance, a rivet member 23. It is seen that, if excess pressure develops in the radiator tank, the gasket 28 and the other members described will be lifted against the action of the spring 25 to provide pressure relief.

A float cage or housing 33 is provided, having a plurality of legs 33a, 330, each affixed to the flange member 29. The cage 33 in this embodiment is constructed of wire or rods and provides an open enclosure for a float 31 and a permanent magnet 32 mounted on and afiixed to the float.

The float 31 can be in a variety of shapes, but it desirably includes a conical or similar segment so that stability in floating is achieved, and the top-heavy effect of the magnet 32 is compensated for. When the coolant level in the radiator is low, the float descends to the lowermost position within the cage 33 as shown.

The second magnet 36 is positioned within a second housing 24 and has aflixed thereto an indicator stem 37. The stem projects through an aperture 38 in the cap, the aperture in this embodiment being in the rivet 23 joining the top member 21 and the housing 24.

Elements of the cap in general are made of non-ferrous material such as brasses, particularly those elements between the first and second magnets. In any case, a material or materials with no magnetic susceptibility is necessary in this zone, to permit the necessary inter-reaction of magnetic forces between the two magnets 32, 36.

In functioning, when the radiator is properly filled with coolant, the float 31 and the first magnet 32 are elevated by the liquid to a position at or near the top of the cage 33. In accomplishing this position, the first magnet 32 repels upwardly the second magnet 36 which moves the indicator pin 37 to a distended position, thus signaling to an observer that no additional coolant is required.

When the coolant is low, the float 31 and first magnet 32 are in the low position shown in the cage 33, and the second magnet 36 and the stem 37 are similarly in a vertically retracted position, thereby signaling the need for coolant addition.

In further embodiments of the invention provision is made for the second magnet-indicating means assembly to perform a further function of providing for a manual or at will relief of the normal pressure on the coolant system, in addition to providing the signaling or level-indicating function already described. In the most preferred of such embodiments, in accomplishing the pressure relief function, the indicating stem also temporarily functions as a closure to fully safeguard the operator from excaping vapor and hot liquid.

An embodiment of this particular character is illustrated by FIG. 2, which is a sectional view of a portion of the full assembly showing the parts and inter-relation thereof peculiar to this type of the invention.

Referring to FIG. 2, the second magnet 46 and stem 47 assembly in this embodiment is positioned with the stem 3 47 slidable in an aperture 48 in the lid portion 41 of the assembly. The aperture 48 has an upwardly divergent portion 49, and the stem 47 is topped by an enlarged head portion 52, with a connecting segment 51 which has a configuration for seating in the conical portion 49 of the aperture 43.

In this embodiment a vacuum release is provided which includes a valve cup 64, a valve stem 65, and a valve spring 66. In normal operating, the valve cup 64 is urged against a second gasket 61, and pressure is retained in the radiator. The second gasket is smaller than the interior opening of the primary gasket 60 to provide an opening for securing the cage legs 62a, 620 to the plate member 58.

In this embodiment the spring 66 is of thin flexible metal, having an elongated oval cross-section, with a gap in one side above the aperture 59. It will be understood that the spring is of relatively narrow width, so as not to impede flow of vapors into the interior of the housing 44 when they rise through the aperture 59. Other forms of springs can of course be substituted, for example, a small coil spring concentric with valve stem 65.

The indicating stem 47 of the assembly is of such length that, when fully depressed to provide engagement of the seat 51 against the corresponding seat 49 of the aperture 48, the lowermost portion of the second magnet 46 strikes the pin 65 of the vacuum relief valve assembly and by depressing the assembly, causes the valve plate 64 to part from the gasket 61. Vapors under pressure are thus permitted to flow around the margin of the valve plate 64, and through the aperture 59, around the valve stem 65. Slots 43a, 43b in the housing 44, or similar openings, permit the vapors to escape from the housing 44 to the nozzle interior from whence they are discharged through an overflow tube as illustrated by FIG. 1.

It will be evident that the proportions of the indicating stem 47 will be accurately defined to achieve the above described pressure release function. The seating action described prevents any stem or vapor from escaping around the stem 47 through the aperture 48.

It will be noted that the inner flange 56 of the flange member 57 is parted from the corresponding portion of the inner cage 44. This is due to the upward retraction of the gasket 60 and associated parts, by engagement of the gasket 60 with the seat of the radiator nozzle, and compression of the pressure relief spring, not shown.

In addition to the pressure release-at-will function of the embodiment above described, the liquid level indicating function is similarly provided. As in other embodiments a float and first magnet, not shown, are provided to co-act with the second magnet as already described.

It will be understood that numerous variations in the particular configurations of the elements of the invention can be made without departing from the scope thereof. For example, instead of an elongated pin indicating means, the second magnet can be associated with appropriate linkage to a needle or pointer for signaling the coolant level.

I claim as my invention:

1. A cap for an automobile radiator or the like for indicating coolant level without removal including a cap top adapted to fasten to a radiator nozzle and support a float and magnet housing assembly,

a float adapted to float on the surface of coolant liquid,

a first permanent magnet attached to the float,

a first housing for the float and first magnet, the housing being permissive of vertical movement of the float and first magnet and open to liquid,

a barrier normally impermeable to fluid above said first magnet and float and supporting said first housr a second permanent magnet above said barrier, said magnet being aligned with a pole opposing a like pole of the first magnet, whereby elevation or depression of the first magnet causes elevation or depression of the second magnet,

a second housing for the second magnet and mounted to said cap top, the housing being permissive of vertical movement of the magnet, and

means responsive to the said second magnet for indicating its elevation above the cap top and thereby the level of coolant in the radiator.

2. The cap of claim 1 further defined in that the indicating means is a pin attached to the second magnet and projecting vertically through an aperture in the cap top.

3. The top of claim 1 further defined in that the normally fluid impermeable barrier includes a valve, and the indicating means is manually shiftable to open said valve for relief of pressure in the radiator.

4. The cap of claim 3 further defined in that the indicating means is a pin attached to the second magnet and projecting through an aperture in the cap top, the valve is a spring closed valve aligned with the second magnet, and the second magnet and indicating pin are proportioned so that extreme downward movement of the pin and magnet cause opening of the valve.

5. The cap of claim 4 further defined in that the pin includes an enlarged section positioned to cause closure of the aperture in the radiator cap top when the pin is depressed sufliciently to open the valve.

References Cited UNITED STATES PATENTS 2,528,791 11/1950 Scoville.

2,968,421 1/1961 Eshbaugh 220-40 3,212,471 10/1965 Willis 11670 3,216,256 11/1965 Barnes 73-306 LOUIS R. PRINCE, Primary Examiner. DANIEL M. YASICH, Assistant Examiner, 

1. A CAP FOR AN AUTOMOBILE RADIATOR OR THE LIKE FOR INDICATING COOLANT LEVEL WITHOUT REMOVAL INCLUDING A CAP TOP ADAPTED TO FASTEN TO A RADIATOR NOZZLE AND SUPPORT A FLOAT AND MAGNET HOUSING ASSEMBLY, A FLOAT ADAPTED TO FLOAT ON THE SURFACE OF COOLANT LIQUID, A FIRST PERMANENT MAGNET ATTACHED TO THE FLOAT, A FIRST HOUSING FOR THE FLOAT AND FIRST MAGNET, THE HOUSING BEING PERMISSIVE OF VERTICAL MOVEMENT OF THE FLOAT AND FIRST MAGNET AND OPEN TO LIQUID, A BARRIER NORMALLY IMPERMEABLE TO FLUID ABOVE SAID FIRST MAGNET AND FLOAT AND SUPPORTING SAID FIRST HOUSING, A SECOND PERMANENT MAGNET ABOVE SAID BARRIER, SAID MAGNET BEING ALIGNED WITH A POLE OPPOSING A LIKE POLE OF THE FIRST MAGNET, WHEREBY ELEVATION OR DEPRESSION OF THE FIRST MAGNET CAUSES ELEVATION OR DEPRESSION OF THE SECOND MAGNET, A SECOND HOUSING FOR THE SECOND MAGNET AND MOUNTED TO SAID CAP TOP, THE HOUSING BEING PERMISSIVE OF VERTICAL MOVEMENT OF THE MAGNET, AND MEANS RESPONSIVE TO THE SAID SECOND MAGNET FOR INDICATING ITS ELEVATION ABOVE THE CAP TOP AND THEREBY THE LEVEL OF COOLANT IN THE RADIATOR. 